/usr/include/CGAL/Homogeneous/basic_constructionsH2.h is in libcgal-dev 4.11-2build1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 | // Copyright (c) 1999
// Utrecht University (The Netherlands),
// ETH Zurich (Switzerland),
// INRIA Sophia-Antipolis (France),
// Max-Planck-Institute Saarbruecken (Germany),
// and Tel-Aviv University (Israel). All rights reserved.
//
// This file is part of CGAL (www.cgal.org); you can redistribute it and/or
// modify it under the terms of the GNU Lesser General Public License as
// published by the Free Software Foundation; either version 3 of the License,
// or (at your option) any later version.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL$
// $Id$
//
//
// Author(s) : Sven Schoenherr
// Stefan Schirra
#ifndef CGAL_BASIC_CONSTRUCTIONSH2_H
#define CGAL_BASIC_CONSTRUCTIONSH2_H
#include <CGAL/Homogeneous/PointH2.h>
#include <CGAL/Homogeneous/LineH2.h>
namespace CGAL {
template <class R>
CGAL_KERNEL_MEDIUM_INLINE
typename R::Point_2
gp_linear_intersection(const LineH2<R>& l1, const LineH2<R>& l2)
{
return typename R::Point_2( l1.b()*l2.c() - l2.b()*l1.c(),
l2.a()*l1.c() - l1.a()*l2.c(),
l1.a()*l2.b() - l2.a()*l1.b() );
}
template <class R>
CGAL_KERNEL_MEDIUM_INLINE
typename R::FT
squared_distance( const PointH2<R>& p, const PointH2<R>& q )
{
typedef typename R::RT RT;
typedef typename R::FT FT;
const RT & phx = p.hx();
const RT & phy = p.hy();
const RT & phw = p.hw();
const RT & qhx = q.hx();
const RT & qhy = q.hy();
const RT & qhw = q.hw();
RT sq_dist_numerator =
phx * phx * qhw * qhw
- RT(2) * phx * qhx * phw * qhw
+ qhx * qhx * phw * phw
+ phy * phy * qhw * qhw
- RT(2) * phy * qhy * phw * qhw
+ qhy * qhy * phw * phw ;
RT sq_dist_denominator = qhw * qhw * phw * phw ;
return FT( sq_dist_numerator ) / FT( sq_dist_denominator );
}
template < class RT, class We>
void
weighted_circumcenterH2( const RT &phx, const RT &phy, const RT &phw,
const We &pwt,
const RT &qhx, const RT &qhy, const RT &qhw,
const We &qwt,
const RT &rhx, const RT &rhy, const RT &rhw,
const We &rwt,
RT &vvx, RT &vvy, RT &vvw )
{
// RT qx_px = ( qhx*qhw*phw*phw - phx*phw*qhw*qhw );
// RT qy_py = ( qhy*qhw*phw*phw - phy*phw*qhw*qhw );
// RT rx_px = ( rhx*rhw*phw*phw - phx*phw*rhw*rhw );
// RT ry_py = ( rhy*rhw*phw*phw - phy*phw*rhw*rhw );
// //intersection of the two radical axis of (qp) and (rp)
// RT px2_py2_rx2_ry_2 =
// phx*phx*rhw*rhw + phy*phy*rhw*rhw - rhx*rhx*phw*phw -
// rhy*rhy*phw*phw - RT(pwt*pwt) + RT(rwt*rwt);
// RT px2_py2_qx2_qy_2 =
// phx*phx*qhw*qhw + phy*phy*qhw*qhw - qhx*qhx*phw*phw -
// qhy*qhy*phw*phw - RT(pwt*pwt) + RT(qwt*qwt);
// vvx = qy_py * px2_py2_rx2_ry_2 - ry_py * px2_py2_qx2_qy_2;
// vvy = rx_px * px2_py2_qx2_qy_2 - qx_px * px2_py2_rx2_ry_2;
// vvw = RT(2) * ( qx_px * ry_py - rx_px * qy_py );
RT a1, b1, c1;
RT a2, b2, c2;
radical_axisH2(phx,phy,phw,pwt,qhx,qhy,qhw,qwt,a1,b1,c1);
radical_axisH2(phx,phy,phw,pwt,rhx,rhy,rhw,rwt,a2,b2,c2);
vvx = b1*c2 - c1*b2;
vvy = c1*a2 - c2*a1;
vvw = a1*b2 - a2*b1;
}
template < class RT , class FT>
void
radical_axisH2(const RT &phx, const RT &phy, const RT &phw, const FT &pwt,
const RT &qhx, const RT &qhy, const RT &qhw, const FT &qwt,
RT &a, RT &b, RT &c )
{
Rational_traits<FT> rt;
RT npwt = rt.numerator(pwt);
RT dpwt = rt.denominator(pwt);
RT nqwt = rt.numerator(qwt);
RT dqwt = rt.denominator(qwt);
a = RT(2) * ( phx*phw*qhw*qhw - qhx*qhw*phw*phw );
b = RT(2) * ( phy*phw*qhw*qhw - qhy*qhw*phw*phw );
c = (- phx*phx*qhw*qhw - phy*phy*qhw*qhw
+ qhx*qhx*phw*phw + qhy*qhy*phw*phw) * dpwt * dqwt
+ npwt*dqwt*phw*phw*qhw*qhw - nqwt*dpwt*phw*phw*qhw*qhw;
}
} //namespace CGAL
#endif // CGAL_BASIC_CONSTRUCTIONSH2_H
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